Something is off with your numbers. You should not be hitting 3k until around 75 with that combo.It gad 3.73 when I bought it 12 years ago. I put in 4.56 a couple years ago.
My wifes yj has 3 speed auto, 4.10s, 35s. Cruises at 3000 rpm at about 60 mph. Blew a rod, complete with a hole in the block when she was on freeway going 65 mph. That was several years ago.
So. I try to keeps rpms down on our 4.0s.